It is known that a crosslinked molded product can be obtained by crosslinking a thermoplastic norbornene resin, which is obtained by ring-opening metathesis polymerization of a norbornene monomer, with a crosslinking agent such as an organic peroxide. For example, Patent Literature 1 discloses a method in which an organic peroxide and a crosslinking aid are added to a thermoplastic hydrogenated ring-opening norbornene resin, the resultant mixture is homogeneously dispersed to obtain a norbornene resin composition, this composition is molded into a film or a prepreg, this film or prepreg is laminated on a substrate, and then the resultant laminate is crosslinked and fused by heat-press molding to obtain a crosslinked molded product. Patent Literature 1 discloses that the crosslinked molded product is useful as an interlayer insulation film, a film for forming a moisture-proof layer and the like.
Patent Literature 1: Japanese Patent Laid-Open No. 6-248164
Patent Literature 2 discloses a method in which a norbornene monomer is metathesis-polymerized in the presence of a ruthenium carbene complex, which is a metathesis polymerization catalyst, and a crosslinking agent, and then post-cured (post-crosslinked). Patent Literature 2 teaches that a highly densely crosslinked polymer can be obtained by this method.
Patent Literature 2: International Publication No. WO 97/03096
Further, Patent Literature 3 discloses that a composite material was obtained by carrying out bulk polymerization of a polymerizable composition which comprises a norbornene monomer, a metathesis polymerization catalyst, a chain transfer agent, and a crosslinking agent to obtain a crosslinkable thermoplastic resin, and then laminating this crosslinkable thermoplastic resin on a substrate or the like and crosslinking the laminated resin.
Patent Literature 3: International Publication No. WO 2004/003052
Further, Patent Literature 4 discloses a method of manufacturing a macromonomer which, in carrying out ring-opening metathesis polymerization, uses a metathesis polymerizable monomer, a metathesis polymerization catalyst, and an allyl compound such as an allyl alcohol, an allyl isocyanate, an allyl isothiocyanate, an allylamine, and an allyl acrylate.
Patent Literature 4: Japanese Patent Laid-Open No. 2001-226466